Nut holding and centering means for nut driving machine



Sept. 18, 1956 R. w. BAILEY ET AL NUT HOLDING AND CENTERING MEANS FORNUT DRIVING MACHINE Filed July 20, 1.955

3 Sheets-Sheet 1 V ATTOR/YEK m l- M F n M m T m J% 6 Y m====EF NNMW/Ar 41 I 7 LII-n1 Sept. 18, 1956 R. w. BAILEY ETAL 2,763,173 I NUT HOLDINGAND CENTERING MEANS FOR NUT DRIVING MACHINE Filed July 20, less :5Shaeis-Sheet 2 E 3: 4 3l I 36 X MM l INVENTORS.

34 w. some) do}; WK'MMS mu- Sept. 18, 1956 R. w. BAILEY ETAL NUT HOLDINGAND CENTERING MEANS FOR NUT DRIVING MACHINE Filed July 20, 1955 5Sheets-Sheet 3 INVENTORS.

Roy w. BAILEY United States Patent ice NUT HOLDING AND CENTERING MEANSFOR NUT DRIVING MACHINE Roy w. Bailey and John T. Faull, Detroit, Mich.,assignors to Detroit Power Screwdriver Company, Detroit, Mich., acorporation of Michigan Application July 20, 1953, Serial No. 368,859

11 Claims. (Cl. 81--54) The present invention pertains to a novel nutdriving machine, and the principal object of the invention is to providea construction that is operated by a slidable and rotatable spindle of astandard machine tool.

Another object of the invention is to provide a relatively simple,inexpensive and efiective construction for the purpose set forth. Afurther object is to provide a mechanism having a receiver for the nutto be driven, with means for righting a nut that does not lie properlyseated in the receiver. Still another object is to provide means forpositively retaining a nut in a downwardly facing wrench while beingdelivered to the Work piece.

In the accomplishment of these objects, a wrench is mounted on thespindle of the described machine, and in the wrench is fitted aspring-backed pilot pin. Opposite the free end ofthe pin is a nutreceiver consisting of split sections. The pilot pin has lateral play inits mounting and has a pointed tip, whereby the pin will right a nutthat is not squarely seated in the receiver.

After the pilot pin has passed through the nut, the wrench comes downover the nut. The pin carries a lengthwise spring wire bowed outwardlyto hold the nut in a downwardly facing wrench.

When the wrench bears upon the nut in the receiver, the pressureinitiates a cam action as it spreads the receiver sections and permitsthe wrench and nut to pass between them to the work. The same pressureis partially opposed by another spring, whereby the nut is positivelyinserted in the wrench against the tension of the bowed spring.

The invention is fully disclosed by way of example in the followingdescription and in the accompanying drawings in which Figure 1 is anelevation of the device, partly in section, showing the initialengagement with the nut;

Figure 2 is a similar elevation, partly broken away, showing an advancedposition;

Figure 3 is a detail of Figure 2, in section;

Figure 4 is another elevation, partly in section, showing a moreadvanced position;

'Figure 5 is an elevation, partly in section, showing the nut applied onthe stud;

Figure 6 is a section on the line 6-6 of Figure 3, showing the nutreceiver in plan view and without the internal parts;

Figure 7 is a detail elevation at right angles to Figure 1;

Figure 8 is a plan section on the line 88 of Figure 2 with the fixed arm1 omitted, and

Figure 9 is an enlarged detail section showing the bowed spring.

Reference to these views Will now be made by use of like characterswhich are employed to designate corresponding parts throughout.

In Figure 1 is shown a fixed horizontal arm I extending from the post orother part of an upright machine such as a drill press. A verticalspindle 2 passes slidably through the arm and is driven by suitablemeans. On

2,763,173 Patented Sept. 18, 1

the lower end of the spindle is screwed an adapter sleeve 3, and on thelower end of the sleeve is screwed a bit or socket wrench 4.- It will beunderstood that the sleeve and the wrench may be furnished in varioussizes according to the dimensions of the nut to be driven.

A coil spring 5 is inserted in the sleeve 3, extending into and beingseated in the spindle at 6 as shown in Figure 5. Against the lower endof the spring is assembled a pilot pin 7 having a collar 8 engaged bythe lower end of the spring. An internal shoulder 9 on sleeve 3 screwedinto the bit retains the pilot pin by extending under the collar 8. Thepin has lateral play or looseness in the enclosing parts and is normallyheld co-axial by a slightly bowed spring wire 10 inserted in alengthwise notch 11 from end to end and anchored by having its upper endbent at a right angle and inserted crosswise in the pin at 12.

Directly below the arm 1, the spindle 2 is surrounded by a block 15having a bushing 15. From the block are pivotally suspended two opposedfingers 16 mounted on parallel pivot pins 17 so that they may swing awayfrom each other. A compressed coil spring 18 is fitted between the endsof the fingers, above the pivot pins, to bring the lower ends of thefingers together. The lower ends of the fingers carry split halves 19 ofa nut receiver that lies directly below the pilot pin 7. The receiver isfed with single nuts from a chute 20 which is controlled by a suitableescapement mechanism as known in the art.

A rod 21 is fixedly suspended from the arm 1, lying adjacent to thefingers 16 and midway between them. On the lower end of the rod 21 issecured a cam block 22 having a pair of opposed downwardly slopingshoulders or cam surfaces 23. Pins 24 projecting from the fingers 16engage the shoulders 23 and cause the split sections 19 to spread apartwhen the fingers 16 are moved downward by the means presently to bedescribed.

Another rod 25-is fastened in a split clamp 26 (Figure 7) on the block15 and extends upwardly and slidably through the arm 1. A split collar27 is secured on the rod 26 at some distance above the arm 1, and a coilspring 28 surrounds the rod between the collar 27 and the top of the arm1.

In the operation of the device, the spindle 2 and .parts carried at thelower end thereof are moved downward by means known in the art andtherefore not illustrated. The finger carrying block 15 does not moveinitially with the spindle since it is not rigidly attached thereto.

The nut to be driven may have entered the receiver 19 in uprightposition. However, the operation may be described more completely withreference to Figure l in which a nut 31 has settled in an oblique orunseated position in the receiver. Also, the nut has lateral play in thespace in which the wrench 4 is to be received in the receiver 19. Thisspace would be relatively wider than shown, where a heavier wrench isrequired for applying a greater torque. Another consideration involvedin the alinement of the nut with the wrench is that some of the nuts maycome through with an eccentric tapped hole. The loose or floating pilotpin 7 with its rounded tip 7 finds the hole in the nut and brings itinto co-axial relation to the wrench for driving as shown in Figures 2and 3. As the pilot pin 7 continues to descend, it finds its way intothe hole of the nut by reason of the pointed end 7 of the pin and theangular displacement permitted by the looseness of the pin in thesurrounding parts at 32. as previously stated. Continued downwardmovement of the pin 7 eventually rights the nut, since the angularmovement of the pin is limited; and the wrench 4 works its way on thenut while the pin 7 passes through an opening 33 in the bottom of thereceiver 19. An adapter 34 below the retaining shoulder 9 then bearsupon the nut as in Figures 2 and 3 and establishes a rigid connectionbetween the spindle 2 and the block 15 through the nut 31, the sections19 and the fingers 16.

As the block 15 moves downward with the spindle, the spring 28 becomescompressed and exerts an upward or retarding force on the receiver 19.The resulting resistance of the receiver to downward movement forces thenut positively into the wrench 4 against the tension of the bowed springwire 10. Some nuts do not require the described action ofspring 28.' Thelarge majority of nuts, however, are not initially engaged by the wrench4 in an alined relation. The spring 28 provides a cushion or resilientrelation between the sleeve .3 and the block 15 carrying the receiver19. If not for this cushion and the time interval permitted thereby, theend of the wrench 4 would merely engage the top of the nut and push itthrough the receiver 19 in the manner presently to be described. In thiscondition the nut would be held by the bowed wire 10 and would crossthread on the stud 35 or cause other damage.

Continued downward movement of the spindle 2 causes the pins 24 to rideon the cam shoulders 23 to spread the receiver sections 19 and permitthe wrench and nut 31 to pass between them as in Figures 4 and 7. Thebowed spring wire It holds the nut from falling out of the wrench, as mybe seen in Figure 4.

When the pilot pin 7 has been stopped by engaging the end of a stud 35on a table 36, the spring permits the spindle to continue downward whilerotating the nut on the stud as shown in Figures 4 and 5. During therelative movement of the spindle and pin 7, the spring 5 in the spindlehas become compressed. When the spindle is raised, the spring-pressedparts are returned to their starting position.

Although a specific embodiment of the invention has been illustrated anddescribed, it will be understood that various alterations in the detailsof construction will be made without departing from the scope of theinvention as indicated by the appended claims.

What we claim is:

l. in a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, a block slidable relatively to said spindle, aresilient cushion between said block and said frame piece and normallyholding said block against sliding on the working stroke, a pair offingers pivotally suspended from said block, nut receiving sectionscarried by said fingers and forming a nut receiver normally disposedaxially adjacent to said pin, whereby said block slides against thepressure of said cushion through pressure of said wrench on a nut seatedin said receiver, a fixed cam block adjacent to said fingers, means onsaid fingers engageable with said cam block to spread said fingers andseparate said sections on pressure of said wrench on a nut seated insaid receiver, said pin being movable with said spindle, through itsbacking spring, to penetrate the bore of a wrench-enclosed nut in saidretainer, and means on said pin for holding such nut after it and thewrench have passed between the separated receiver sections.

2. In a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, said pin having lateral play in said spindle andwrench, a block slidable relatively to said spindle, a resilient cushionbetween said block and said frame piece and normally holding said blockagainst sliding on the working stroke, a pair of fingers pivotallysuspended from said block, nut receiving sections carried by saidfingers and forming a nut receiver normally disposed axially adjacent tosaid pin, whereby said block slides against the pressure of said cushionthrough pressure of said wrench on a nut seated in said receiver, afixed cam block adjacent to said fingers, means on said fingersengageable with said cam block to spread said fingers and separate saidsections on pressure of said wrench on a nut seated in said receiver,said pin being movable with said spindle, through its backing spring, topenetrate the bore of a wrench-enclosed nut in said retainer, and meanson said pin for holding such nut after it and the wrench have passedbetween the separated receiver sections.

3. In a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, said pin having lateral play in said spindle andwrench, a block slidable relatively to said spindle, a resilient cushionbetween said block and said frame piece and normally holding said blockagainst sliding on the working stroke, a pair of fingers pivotallysuspended from said block, nut receiving sections carried by saidfingers and forming a nut receiver normally disposed axially adjacent tosaid pin, whereby said block'slides against the pressure of said cushionthrough pressure of said wrench on a nut seated in said receiver, afixed cam block adjacent to said fingers, means on said fingersengageable with said cam block to spread said fingers and separate saidsections on pressure of said wrench on a nut seated in said receiver,and an outwardly acting spring mounted lengthwise on the outside of saidpin for retaining a nut on the pin, said pin being movable through itsbacking spring, to penetrate the bore of a wrench-enclosed nut in saidretainer, said outwardly acting spring being adapted to hold such nutafter it and the wrench have passed between the separated receiversections.

4. In a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, a block slidable relatively to said spindle, aresilient cushion between said block and said frame piece and normallyholding said block against sliding on the working stroke, a pair offingers pivotally suspended from said block, nut receiving sectionscarried by said fingers and forming a nut receiver normally disposedaxially adjacent to said pin, whereby said block slides against thepressure of said cushion through pressure of said wrench on a nut seatedin said receiver, a fixed cam block adjacent to said fingers and havingopposed slopingcam shoulders, pins on said fingers and engageable withsaid shoulders to spread said fingers and separate said sections onpressure of said wrench on a nut seated in said receiver, said pin beingmovable with said spindle, through its backing spring, to penetrate thebore of a wrench-enclosed nut in said retainer, and means on said pinfor holding such nut after it and the wrench have passed between theseparated receiver sections.

5. In a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, said pin having lateral play in said spindle andwrench, a block slidable relatively to said spindle, a resilient cushionbetween said block and said frame piece and normally holding said blockagainst sliding on the working stroke, a pair of fingers pivotallysuspended from said block, nut receiving sections carried by saidfingers and forming a nut receiver normally disposed axially adjacent tosaid pin, whereby said block slides against the pressure of said cushionthrough pressure of said wrench on a nut seated in said receiver, afixed cam-block adjacent to said fingers and having opposed sloping camshoulders, pins on said fingers and engageable with said shoulders tospread said fingers and separate said sections on pressure of saidwrench on a nut seated in said receiver, said pin being movable withsaid spindle, through its backing spring, to penetrate the bore of awrench-enclosed nut in said retainer, and means on said pin for holdingsuch nut after it and the wrench have passed between the separatedreceiver sections.

6. In a nut driving machine, a fixed frame piece, a slidable androtatable spindle therein, a spring-backed pilot pin slidably mounted inthe working end of said spindle, a wrench on said spindle andsurrounding said pin, said pin having lateral play in said spindle andwrench, a block slidable relatively to said spindle, a resilient cushionbetween said block and said frame piece and normally holding said blockagainst sliding on the working stroke, a pair of fingers pivotallysuspended from said block, nut receiving sections carried by saidfingers and forming a nut receiver normally disposed axially adjacent tosaid pin, whereby said block slides against the pressure of said cushionthrough pressure of said wrench on a nut seated in said receiver, afixed cam block adjacent to said fingers and having opposed sloping camshoulders, pins on said fingers and engageable with said shoulders tospread said fingers and separate said sections on pressure of saidwrench on a nut seated in said receiver, said cushion being resilientand compressible, whereby to exert a force on said receiver to insertthe nut in the wrench, and an outwardly acting spring mounted lengthwiseon said pin for retaining a nut on the pin, said pin being movablethrough its backing spring, to penetrate the bore of a wrench-enclosednut in said retainer, said outwardly acting spring being adapted to holdsuch nut after it and the wrench have passed between the separatedreceiver sections.

7. In a nut driving machine, a slidable and rotatable spindle, aspring-backed pilot pin slidably mounted in the working end of saidspindle, a wrench on said spindle and surrounding said pin, said pinhaving lateral play in said spindle and wrench, a pair of nut receivingsections supported axially adjacent'to said pin and forming a nutreceiver, said sections having bottom parts adapted to support a nutloosely in the receiver, means operable by pressure of said wrench on anut seated in said receiver for separating said sections to permitpassage of said wrench between them, said pin being movable with saidspindle, through its backing spring, to penetrate the bore of awrench-enclosed nut in said retainer, and means on said pin for holdingsuch nut after it and the wrench have passed between the separatedreceiver sections.

8. In a nut driving machine, a slidable and rotatable spindle, aspring-backed pilot pin slidably mounted in the working end of saidspindle, a wrench on said spindle and surrounding said pin, a pair ofnut receiving sections supported axially adjacent to said spindle andforming a nut receiver, means operable by pressure of said wrench on anut seated in said receiver for separating said sections to permitpassage of said wrench between them, and spring means resisting movementof said receiver by spindle pressure, whereby to exert a force on saidreceiver to insert the nut in the wrench, said pin being movable withsaid spindle, through its backing spring, to penetrate the bore of awrench-enclosed nut in said retainer, and means on said pin for holdingsuch nut after it and the wrench have passed between the separatedreceiver sections.

9. In a nut driving machine, a slidable and rotatable spindle, aspring-backed pilot pin slidably mounted in the working end of saidspindle, a wrench on said spindle and surrounding said pin, said pinhaving lateral play in said spindleand wrench, a pair of nut receivingsections supported axially adjacent to said spindle and forming a nutreceiver, means operable by pressure of said Wrench on a nut seated insaid receiver for separating said sections to permit passage of saidwrench between them, and spring means resisting movement of saidreceiver by spindle pressure, whereby to exert a force on said receiverto insert the nut in the wrench, said pin being movable with saidspindle, through its backing spring, to penetrate the bore of awrench-enclosed nut in said retainer, and means on said pin for holdingsuch nut after it and the wrench have passed between the separatedreceiver sections.

10. In a nut driving machine, a slidable and rotatable spindle, aspring-backed pilot pin slidably mounted in the working end of saidspindle, a wrench on said spindle and surrounding said pin, a pair ofnut receiving sections supported axially adjacent to said pin andforming a nut receiver, said sections having bottom parts adapted tosupport a nut loosely in the receiver, means operable by pressure ofsaid wrench on a nut seated in said receiver for separating saidsections to permit passage of said Wrench between them, and an outwardlyacting spring mounted lengthwise on the outside of said pin forretaining a nut on the pin, said pin being movable through its backingspring, to penetrate the bore of a wrench-enclosed nut in said retainer,said outwardly acting spring being adapted to hold such nut after it andthe wrench have passed between the separated receiver sections.

11. In a nut driving machine, a slidable and rotatable spindle, aspring-backed pilot pin slidably mounted in the working end of saidspindle, a wrench on said spindle and surrounding said pin, said pinhaving lateral play in said spindle and wrench, a pair of nut receivingsections supported axially adjacent to said spindle and forming a nutreceiver, means operable by pressure of said wrench on a nut seated insaid receiver for separating said sections to permit passage of saidwrench between them, spring means resisting movement of said receiver,whereby to exert a force on said receiver to insert the nut in thewrench, and an outwardly acting spring mounted lengthwise on the outsideof said pin for retaining a nut on the pin, said pin being movablethrough its backing spring, to penetrate the bore of a wrench-enclosednut in said retainer, said outwardly acting spring being adapted to holdsuch nut after it and the wrench have passed between the separatedreceiver sections.

References Cited in the file of this patent UNITED STATES PATENTS851,181 McMurtry Apr. 23, 1907 1,575,149 Craig Mar. 2, 1926 2,281,190Bertalan Apr. 28, 1942 2,301,438 Moeller Nov. 10, 1942 2,509,123 Baileyet al May 23, 1950 2,566,257 Strunk Aug. 28, 1951

